Akein Scott was the first suspect in the investigation to be apprehended. He was arrested late Wednesday night at a house in eastern New Orleans. According to sheriff's records released Thursday, Akein was identified by a witness in a photo lineup. He was arrested on 20 counts of attempted second-degree murder.

Shawn Scott, 24, was also arrested in the incident. Police said Shawn is the brother of Akein Scott.

Police called Shawn a career criminal. He was also booked on 20 counts of attempted second-degree murder, police said. Officers arrested Shawn Scott about 7 a.m. in New Orleans East in the 9600 block of Haynes Boulevard.

Police said Shawn attempted to flee out of the back door of the home, but was quickly apprehended.

According to police, the brothers are involved in the Frenchman and Derbigny Boys gang.

Police also confirmed at a noon news conference that four others were arrested on charges of harboring Akein Scott and accessory after the fact.

At the time of his arrest, Shawn Scott had four warrants out for his arrest, including illegal carrying of a weapon, possession with the intent to distribute a controlled, dangerous substance and traffic attachments. He was currently on parole for possession with the intent to distribute heroin and possession of cocaine until December 2015.

According to the NOPD, he was previously arrested on charges of resisting an officer, criminal trespass, traffic violations, possession of marijuana, warrants, possession of crack cocaine, possession of heroin and attachments.

According to the NOPD, Justin Alexander has been previously arrested on charges of distribution of a schedule 1 narcotic and distribution of a control dangerous substance within 1,000 feet of a school. He also has an outstanding municipal court attachment.

Nekia Youngblood has been previously arrested on a charge of driving while intoxicated.

"We all came back here, to make it clear that the culture of death and violence on the streets of New Orleans is unnatural," Mayor Mitch Landrieu said. "We will not let up. The rules of the game have changed on the streets of New Orleans."

The shooting injured a total of 20 people, according to the arrest warrant released on Thursday. Originally, 19 people were reported injured in the gunfire that erupted during a second-line parade. Three people are still listed in critical condition.

Akein Scott appeared in magistrate court at 10 a.m. and smiled as the charges against him were read. His bond was set at $10 million.

"The people of New Orleans chose to be with us and not with the coward who fired into this crowd," NOPD Supt. Ronal Serpas said.

INVESTIGATIONS... BOND WAS SET AT 10 MILLION DOLLARS FOR THE PRIME SUSPECT -- 19-YEAR-OLD AKEIN SCOTT -- AFTER HE WAS ARRESTED LAST NIGHT AT A HOME IN NEW ORLEANS EAST. FOUR OTHERS INSIDE THE HOME WERE ALSO TAKEN INTO CUSTODY FOR HELPING SCOTT HIDE OUT... AND NOW... POLICE ARE SAYING A SECOND SUSPECT HAS BEEN ARRESTED. THIS AS WE'VE LEARNED A TOTAL OF 20 PEOPLE WERE HURT DURING THE MOTHER'S DAY SHOOTING. THE MAYOR AND POLICE CHIEF HAVE CALLED A NEWS CONFERENCE -- LET'S LISTEN IN THIS IS EXCLUSIVE VIDEO OF AKEIN SCOTT BEING TAKEN INTO @@úúppxx÷÷ @@úúppxx÷÷ @@úúppxx÷÷ @@úúppxx÷÷ EAST. SCOTT WAS ARRESTED BY FEDERAL MARSHALS -- AND THE NOPD SPECIAL TASK FORCE SHORTLY AFTER TEN OCLOCK LAST NIGHT -- AND ENDS A 3-DAY MANHUNT THAT SPANNED THE ENTIRE CITY OF NEW ORLEANS... HE IS THE PRIME SUSPECT.. BUT TODAY WE ALSO LEARNED THAT NEW ORLEANS POLICE HAVE A SECOND SUSPECT IN CUSTODY.. WE ALSO HAVE VIDEO OF SCOTT AS WAS BROUGHT INTO CENTRAL LOCKUP - BEFORE HE WAS BOOKED.. A VERY QUIET SCOTT --- BUT PLENTY OF NEW DEVELOPMENTS TODAY ... LET'S GO OUT LIVE TO WDSU I-TEAM REPORTER TRAVERS MACKEL.